Devices that automatically perform excavation work have been introduced in excavation devices such as a hydraulic shovel and a bulldozer. It is required to perform an operation in which excavation is performed by recognizing positions of a bucket and an excavated material and moving the bucket to the excavated material in order to automatically perform the excavation work. Sensors that measure an angle of the bucket, the amount of stroke, and an angle of an arm or a boom have been developed as a means for measuring the position of the bucket. However, it is difficult to recognize an excavation target material using such sensors. For example, it is difficult to set a position and a shape of an excavated material in the case of excavating coal or iron ore in a mine, and thus, it is necessary to recognize the position and shape in real time at the time of performing work.
Meanwhile, disclosed is a technique in which an excavation device is equipped with a stereo camera to recognize external world. A work amount measurement device, which is disclosed in PTL 1, is configured to photograph a bucket after excavation and after releasing of earth so as to calculate a capacity, and to measure the amount of excavation from each difference of the capacity. In addition, a calibration system of a hydraulic shovel in PTL 2 is configured to photograph a work tool, which is moved to a reference point, using a stereo camera so as to measure a position thereof, and to perform calibration of an angle sensor of a boom or an arm.